Just finished my green belt project analyzing how effective web analytics is in identifying applications no longer required by IT (and should be archived) . the project went well I had some interesting data to show for it and it def drove a decision.
Some advice to others looking to start a GB project I'd like to mention a couple of general things I learned from setting up and running mine:
Don't boil the ocean - Improve an existing process as your green belt project.
Use Six Sigma tools to measure process output and identify where failures impact results (FMEA, C&E, etc).
Apply Lean Thinking to a step that has a lot of failure.
Measure improvement using Six Sigma tools (remesure your failure rate / speed / or what every you has as the cause of your failure).